Fuels and ignition aids made of modified, renewable raw materials

ABSTRACT

A fuel is described comprising a material containing cellulose or hemicellulose as well as of fats and/or oils stemming from secondary or cascade utilization or containing these, wherein the fats and oils are obtained by processing waste and recycling materials.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national stage application (under 35 USC § 371) ofPCT/EP2017/071074, filed Aug. 22, 2017, which claims benefit of Germanapplication No. 10 2016 115 664.7, filed Aug. 24, 2016, the contents ofeach of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION Technical Field and State of the Art

The present invention relates to fuels and ignition aids made ofrenewable raw materials and/or organic recycling or waste materialswhich are provided with various additives aimed at improving theirproperties. Moreover, the invention relates to the use of fats and oilsstemming from cascade or secondary utilization in order to produce suchfuels and ignition aids as well as special types or commercial forms ofthese fuels and ignition aids.

Not least from the standpoint of climate protection, there is a need togreatly reduce the consumption of fossil fuels such as, for instance,petroleum, coal and gas, in order to generate power. For this reason,fuels from renewable organic raw materials are acquiring ever-greatersignificance. In this context, examples include straw, wood as well aspaper and cardboard that are made mainly of these raw materials.

The state of the art puts forward numerous proposals for improving thecombustion properties, increasing the heating value and reducing theslag formation associated with these fuels. For instance, German patentapplication DE 10 2004 042 659 A1 discloses a fuel pellet made ofprimary waste and recycling material obtained from grain harvesting andgrain processing, to which lime is admixed in order to reduce slagformation.

German utility model DE 20 2006 014 651 U1 describes a fuel whichcontains natural organic oils and fats as well as sodium perborate inorder to increase the heating value and to reduce slag formation.

German utility model DE 08212935 U1 relates to fuel briquettesconsisting of a mixture of rubber particles, wood shavings and paperscraps held together by means of a cellulose adhesive. In this process,the particles containing cellulose are impregnated with oil or wasteoil.

Fuel briquettes which are made on the basis of wood and whose productionon a briquetting machine involves the admixture of oily vegetable matteras the binding agent and needles or leaves as the fragrance additive areproposed in German patent application DE 196 31 762 A1.

German utility models DE 20 15 005 372 U1 and DE 20 2016 102 694 U1relate to ignition aids which consist of dried pine cones and sprucecones that are combined with cardboard or paper and a combustible fat,or in which the fuel element is made of a cotton wool-like cellularmaterial that has been impregnated with wax.

In view of the current and increasing scarcity of raw materials, it isnecessary to develop new processing modalities, application areas andre-utilization possibilities for waste materials so that these can bere-used while entailing the lowest possible losses in quality. The trendreversal observed in all realms of society, namely, the realization thatwaste materials stemming from primary application areas should beconsidered as re-useable materials that can be returned to the economiccycle is based not only on environmental considerations but also to anincreasing extent on economic and financial interests.

For example, European patent specification EP 2 109 660 B1 describes amethod for the production of starting materials or additives forcosmetics, pharmaceuticals and/or combustion materials or fuels forheating systems or internal combustion engines as well as for candles orthermal storage materials. In this process, contaminated materialsclassified as C1, C2 or C3 under EU Regulation 1774/2002 or EURegulation 1069/2009 are processed for the purpose according to theinvention specified there.

In the case of the combustible materials known from the state of theart, their ignition or combustion properties are modified withpetrochemical substances or with basic materials stemming from primaryproduction such as fats and oils preferably consisting of palm oil orrapeseed oil, whereby these substances are then no longer available fortheir actual intended purpose. The suggested use of secondary materialsin the form of waste oil and rubber particles is likewise unsuitable forheating and combustion purposes since this is associated withunacceptable environmental pollution in the form of toxic substances.Finally, when it comes to combustible products from the state of theart, their handling and portioning properties are often very limited,which detrimentally affects their use in various cases.

International patent application WO 2012/068 640 A1 discloses a fuel forCO combustion with coal in a coal-burning power plant entailing low CO₂emissions, having a certain percentage of waste oil and a percentage ofcellulose material that serves to absorb the waste oil. This waste oilcan consist of recycling materials or waste materials from varioussources.

European patent application EP 1 600 493 A2 discloses the packaging ofwood or of materials containing wood in a bag or pouch made of linen inorder to make them easier to use and to ignite. In addition, this bag orpouch is impregnated with an oil. The oil that is used is high-gradenatural or vegetable oils, which can also be perfumed.

Before this backdrop, the present invention was based on an objective ofputting forward fuels and the like that, if at all possible, are madecompletely of sustainable and regionally available raw materials. Inthis context, when it comes to the use according to preferredembodiments of the invention, these raw materials should not competewith another use, for instance, as components of the food chain. Afterall, an objective of the present invention was to put forward fuels andthe like which, in spite of the above-mentioned boundary conditions,display excellent ignition and combustion properties while also allowingthe simplest handling possible.

This objective is achieved by the present invention as described below.

SUMMARY OF THE INVENTION

A fuel is formed by combining one or more oils or fats sourced fromwaste and recycling materials stemming from secondary or cascadeutilization that have been hydrogenated with a cellulose orhemicellulose or mixture of cellulose and hemicellulose. The waste andrecycling materials may be used cooking fats, returns and reject batchesstemming from the food and cosmetics industries, used vegetable oils,animal fats from slaughterhouse waste, and mixtures thereof. Besideshydrogenation, other chemical and/or physical processing may be done onthe waste and recycling materials, such as liquefying, filtering,enriching, and purifying, such as by distillation. The materialcontaining cellulose or hemicellulose may comprise wood residues, orwaste and recycling matter from grasses (Poaceae), or waste andrecycling matter from sedges (Cyperaceae), or grain cultivation or grainprocessing, and mixtures thereof. The cellulose or hemicellulosematerials may be admixed with the hydrogenated waste and recyclingmaterials, such as by spraying or immersing or otherwise being mixedtherewith, to form the fuel.

DETAILED DESCRIPTION

The raw materials (raw materials A) for the fuels and ignition aidsaccording to the invention (also together referred to as fuels) are, onthe one hand, substances stemming from secondary or cascade utilization(waste and recycling materials which can be readily burned as suchwithout releasing environmentally harmful substances in this process.These are preferably cellulose or hemicellulose substances. Preferredexamples are wood or wood residues in the form of sawdust, shavings,fibers, small pieces or wood dust, which can also be compressed andmixed together with each other. Likewise included here are paper andcardboard of any grade as well as waste and recycling materials stemmingfrom grain cultivation and grain processing such as, for instance,chaff, threshing waste, chips, dust, flour and straw. In this context,the term “straw” is used as a collective term for threshed and/or driedstalks and leaves of plants, protists of any type and size such as, forexample, grains, oily plants, fibrous plants, legumes, etc. According tothe invention, these are preferably plants that grow annually and thusespecially meet the requirement of sustainability. According to theinvention, straw is also used in the form of (twisted) straw ropes.

The list of raw materials A presented above is not complete and anyperson skilled in the art who has knowledge of the present invention candirectly augment this list with additional substances and materials thatare suitable for the purpose according to the invention.

The above-mentioned materials are characterized by a high energy yieldwhen they are burned, but they need to be improved in terms of theirignition and combustion behavior as well as ease of handling.

These raw materials A are improved or modified according to theinvention with an eye towards the above-mentioned criteria by theaddition of oils and fats or their derivatives or constituents such asfatty acids, fatty alcohols, glycerin from the secondary sector or fromcascade utilization. These fats and oils are constituents of, orthemselves constitute, waste or recycling materials from cascade orsecondary utilization and normally have to be disposed of at greateffort or collected for further utilization (raw materials B). For theobjectives of the present invention, the term “cascade utilization”refers to the preceding single or multiple use of a substance ormaterial in identical or different applications.

However, as a rule, it is not possible to directly make use according tothe invention of the raw materials B since undefined substance mixturesare obtained from the waste sector of secondary or cascade utilization(e.g. used cooking fats, returns and reject batches from the food andcosmetics industries, heavily contaminated C1 to C3 materials that fallunder EU Regulation 1774/2002 or EU Regulation (EC) 1069/2009, usedvegetable oils and animal fats from slaughterhouse waste as well as fatsand oil from the animal-feed sector such as fish and crustacean oils,corn oil, olive oil, cotton-seed oil, soy oil, coconut oil, palm oil,sunflower oil and rapeseed oil). Moreover, the heat changes broughtabout by the processing give rise to polymerization products and/orbreakdown products. Aside from the undefined chemical composition, it isalso often the case that the physical parameters such as, for instance,an excessively low melting point of such substance mixtures stand in theway of their use according to the invention. If the melting point of theoil and fat component is too low, this makes processing, handling andstorage of the thus-produced fuels all the more difficult, especially athigh temperatures.

For this reason, the waste and recycling materials that can be usedaccording to the invention and that stem from secondary or cascadeutilization have to be processed prior to their being used. For thispurpose, preferably the following method steps are suitable which arepreferably all carried out in the indicated sequence. Depending on thecondition and the quality of the available fat and oil component, it isalso possible to dispense with one or more individual steps.

The material on hand from secondary or cascade utilization is liquefiedand optionally fed through a filter system in order to eliminate anyforeign matter present.

In a mixing reactor, the desired fat and oil materials are enriched bymeans of sorption (media: zeolites, activated carbon, saw shavings,etc.) at a phase boundary and washed for a time period of preferably 15to 45 minutes until the possibly acidic washing water is completelyclear. The temperature during this procedure—which sometimes has to berepeated one or more times—is preferably approximately 70° C. to 80° C.

This is usually followed by another filtration step. During this step,the filter medium (e.g. zeolites) is preferably configured in such a waythat ranges of up to 1.2 μm can be filtered and a lipid permeability isachieved and maintained. The product of this filtration can, ifnecessary, undergo step 2 once again, whereby in this case, this iscarried out at temperatures of preferably 50° C. to 110° C.

The product of the preceding method steps can undergo distillation inorder to perform further (fine) purification. For instance, in thismanner, it is possible to separate out undesired olfactorycontamination. Preferably, the distillation is carried out up to an acidvalue of less than 2. This allows the further use according to theinvention of highly broken-down substances stemming from second or thirdutilization. Incremental inspection and sampling are advisable in thiscontext.

Optionally, this can be followed by a hydrogenation step. This isdescribed extensively, for example, in European patent specification EP2 109 660 B1 and serves, on the one hand, to reliably decontaminate theemployed raw materials B, eliminating bacteria, fungi, viruses, etc.(e.g. in the case of C1 to C3 materials) and, on the other hand, thisstep serves to achieve fat hydrogenation by saturating the double bondsas well as to obtain an end product that is as homogeneous as possible.This process is preferably carried out at 200° C. to 280° C. and atpressures of 0.2 MPa to 5 MPa. Sampling and determining the iodine value(preferably, e.g. 1 to 120) make it possible to regulate the desireddegree of hydrogenation. In the realm of the fuels that are to beproduced here, splitting the double bonds has proven to be advantageousin order to prevent spontaneous self-ignition processes, without therebydetrimentally affecting a quick burn-off and clean combustion processes.

A subsequent filtration process can be advantageous for purposes ofremoving any residues of the common hydrogenation catalysts and anyundesired polymerization products that might be present.

The product thus obtained is filled into a thermal storage unit,preferably at temperatures from 25° C. to 100° C. and then stored. As arule, an excessively short cooling time with high temperature gradientsshould be avoided for the processed raw materials B since this can leadto unstable crystal structures which could have a detrimental effect onthe properties of the fuel end products.

The explained method steps 1 to 7 are fundamentally known in the stateof the art. Their configuration and sequence can be easily adapted tothe starting materials in question (raw materials B) by the personskilled in the art.

The processed raw materials B thus obtained preferably have meltingpoints within the range from 30° C. to 60° C.

For the purposes of the invention, the various (processed) raw materialsB can be fundamentally mixed and used in any desired ratio in order toprocess them as well as afterwards. With an eye towards furtherimproving the properties, in certain cases, it can be advisable to admixsmall amounts of primary fats and primary oils to the purified material.

The raw materials B processed according to the invention exhibit apurity and quality that allow their safe use in an array of industriallyas well as non-industrially manufactured products. After appropriateprocessing, they can also be employed in the food and animal-feedsectors. Examples of these are glycerin or substances containingglycerin stemming from cascade utilization, whereby the glycerin can bere-used after the described treatment, for example, in the foodindustry, as solvents and humectants for tobacco and cosmetics and alsoas an ingredient of anti-freeze agents and lubricants. Moreover, thefats, fatty acids and fatty alcohols thus obtained are suitable, forexample, as fuel for combustion machines.

For the production of the fuel according to the invention, the processedraw materials B are admixed to the raw materials A. There arefundamentally no limitations when it comes to the possible combinationsof the raw materials A and the processed raw materials B (both in termsof the composition of the raw materials A and of the processed rawmaterials B as well as in terms of the composition of the combination ofA and processed B). Preference is given to A-to-B ratios within therange from 90:10 to 10:90, especially of approximately 50:50 (allfigures are in % by weight). In this context, the raw materials A canhave been pretreated. This means that these materials can be present inmixed or compressed form as pellets or granules, or else twisted into akind of rope, for instance, in the case of fibers and straw, in order toincrease the energy density. The raw materials A are preferably coatedwith the processed raw materials B, sprayed with the processed rawmaterials B or else immersed into the processed raw materials B. The rawmaterials A and the processed raw materials B can also be mixed togetherand, if applicable, can be subsequently compressed to form pellets orgranules. There are no restrictions whatsoever regarding the way inwhich the raw materials A are mixed with the processed raw materials B.This procedure can be adapted to the materials in question and to theapplication purposes in the best possible manner. The (requisite) degreeof processing of the raw materials B can also vary to a great extent.This ranges from no need for any processing all the way to a completedeployment of all of the method steps described. According to theinvention, this is all encompassed by the terms “processing” or“processed”.

The fuels manufactured according to the invention can be produced andoffered in a wide array of types, for instance, as rope pieces, in theform of briquettes, slabs, cubes, sticks, pellets, granules and as dustsof various grain sizes. Packaging the fuels according to the inventionhas proven to be very advantageous when it comes to their handling andportioning properties, especially for their use as ignition aids suchas, for example, grill lighters and lighters for fireplaces or ceramicheating stoves. In this context, preference is given to packaging inpouches or bags of various sizes which can be described as small, largeor extra large teabags. These, in turn, can be packaged in otherpackaging units (for instance, boxes or crates).

These bags are filled with the raw materials A—which can already but donot necessarily have to have been combined with the processed rawmaterials B. Suitable for this purpose are especially small-sized orfine-grained raw materials A such as, for example, dusts. The bags thusfilled are subsequently sprayed or coated with the processed rawmaterials B or else immersed into the processed raw materials B, so thata fat or oil coating is formed on them. This coating protects the bagand its contents against moisture, so that this kindling material can beignited, for example, during barbecuing, even when it is raining, and itthen reliably burns off. Moreover, this also reduces saturation withhumidity during storage and ensures reliable ignition and burn-offbehavior. In addition, the raw materials A can be mixed in a mixing drumtogether with, for instance, fat granules and subsequently, this mixturecan be filled into the bag by means of a filling station (teabag fillingsystem). Various materials such as, for example, absorbent paper, filterpaper, cellulose, etc. are all well-suited as the wall material of thebags or pouches.

Finally, fragrances and colorants (e.g. cedar oil) and/or otheradmixtures such as, for instance, pyrotechnical agents to generate lighteffects (for example, Cu powder) can be admixed to the fuels accordingto the invention. In this context, usually an amount of 2% to 3% byweight relative to the total fuel should not be exceeded. In most cases,considerably smaller amounts are already sufficient in order to attainthe desired olfactory and visual effects.

The fuels according to the invention are characterized by a reliableignition and burn-off behavior as well as convenient handling andportioning properties. An aspect worth mentioning is the sustainabilityof these fuels since they can be made exclusively out of recycling orwaste materials which, furthermore, are regionally available insufficient quantities and consequently do not have to be transportedover long distances. These fuels or kindling materials are also providedwith a hydrophobic finish, a measure which significantly delays theirdegradation processes and reduces or prevents the release of carbonoxides. The release of carbon monoxide, for example, in storage units orcontainers holding untreated wood pellets, is a problem that should notbe underestimated.

The present invention is not restricted in terms of its configuration tothe embodiments presented here. Rather, several variants are conceivablewhich make use of the solution presented here, even in the case of othertypes of configurations. It will be appreciated by those skilled in theart that changes could be made to the embodiments described abovewithout departing from the broad inventive concept thereof. It isunderstood, therefore, that this disclosure is not limited to theparticular embodiments disclosed, but it is intended to covermodifications within the spirit and scope of the present disclosure asdefined by the appended claims.

1. A fuel, comprising: (i) a material containing cellulose orhemicellulose and (ii) one or more oils or fats, wherein the one or moreoils and fats are sourced from waste and recycling materials stemmingfrom secondary or cascade utilization and have been hydrogenated priorto combining with the cellulose or hemicellulose.
 2. The fuel accordingto claim 1, the waste and recycling materials are selected from thegroup consisting of: used cooking fats, returns and reject batchesstemming from the food and cosmetics industries, used vegetable oils,animal fats from slaughterhouse waste, and mixtures thereof.
 3. The fuelaccording to claim 1, wherein, in addition to hydrogenation, the wasteand recycling materials undergo chemical, or physical or both chemicaland physical processing.
 4. (canceled)
 5. The fuel according to claim 1,wherein the one or more oils and fats are derived from materialsclassified as C1, C2 or C3 under EU Regulation 1774/2002.
 6. The fuelaccording to claim 1, wherein the material containing cellulose orhemicellulose is selected from the group consisting of: wood residues,waste and recycling matter from grasses (Poaceae), waste and recyclingmatter from sedges (Cyperaceae), grain cultivation or grain processing,and mixtures thereof.
 7. The fuel according to claim 6, wherein thewaste and recycling materials from grain cultivation or grain processinginclude chaff, threshing waste, chips, dust, flour or straw.
 8. The fuelaccording to claim 7, in the form of a rope made of straw.
 9. (canceled)10. (canceled)
 11. (canceled)
 12. A method for the production of a fuel,comprising: mixing a material containing cellulose or hemicellulose orboth cellulose and hemicellulose with oils or fats or both oils and fatsthat have been hydrogenated prior to mixing.
 13. (canceled) 14.(canceled)
 15. The method for the production of a fuel of claim 12,wherein mixing is by immersing the material containing cellulose orhemicellulose or both cellulose and hemicellulose into the oils or fatsor both oils and fats.
 16. The method for the production of a fuel ofclaim 12, wherein mixing is by spraying the material containingcellulose or hemicellulose or both cellulose and hemicellulose with oilsor fats or both oils and fats.
 17. The method for the production of afuel of claim 12, further comprising: prior to hydrogenating, liquefyingthe oils or fats or both oils and fats; filtering the liquified oils orfats or both oils and fats; enriching the filtered and liquified oils orfats or both oils and fats by sorption; and distilling the filtered andliquified oils or fats or both oils and fats.